Safety and Efficacy of Percutaneous Morton Neuroma Cryoneurolysis Under Ultrasound Guidance.

PURPOSE: To assess the technical success, safety and early efficacy of Morton neuroma (MN) cryoneurolysis. MATERIALS AND METHODS: Retrospective review of 54 consecutive patients with MN treated with cryoneurolysis after failure of conservative treatment, from September 2022 to June 2023. Outcomes measurements included technical success (defined a successful ultrasound-guided placement of the cryoprobe), procedural safety according to Cirse classification and change in 6 months post-procedure by pain numeric rating scale (pNRS). RESULTS: A total of 59 MN were treated during 55 procedures. Mean procedure duration was 47 min, all patients were discharged 2 h after the intervention. Technical success was 98.1%. No Cirse grade 3, 4 or 5 complication was reported. Three grade 2 complication occurred, including two chilblain-type lesions and one bone insufficiency fracture. At 6 months post-procedure, pNRS score was significantly decreased (2.7 ± 2.2 vs 7.1 ± 1.1) (p < 0.0001), with a mean score decrease of 4.1points. Thirty-two patients (60.4%) reported a complete pain relief, 15 (28.3%) a partial pain relief and 6 (11.3%) no pain relief, or increased pain. CONCLUSION: Cryoneurolysis seems to be safe for the treatment of Morton neuroma. Six-month pain relief is promising and needs to be confirmed at long term.

Anesthetic implications for robot-assisted transaxillary thyroid and parathyroid surgery: a report of twenty cases.

Gasless transaxillary robot-assisted endoscopic thyroid surgery has recently been proposed and developed in South Korea and the United States. Perianesthetic implications and their evolution for 20 patients scheduled to undergo this innovative surgical technique are presented. The anesthetic considerations focus on the length of surgery due to the learning curve, the risk of the ipsilateral arm posture, and postoperative pain evaluation and management.

Effects of laparoscopic pneumoperitoneum and changes in position on arterial pulse pressure wave-form: comparison between morbidly obese and normal-weight patients.

BACKGROUND: Laparoscopic adjustable gastric banding (LAGB) is commonly indicated in morbidly obese patients. There is controversy regarding the hemodynamic effects of pneumoperitoneum (PNP) in obese patients. PNP and changes in body posture have complex effects on venous return that may be detected by respiratory changes in the arterial pressure waveform. The aim of this study was to compare pneumoperitoneum-induced and reverse Trendelenburg (RT) changes in arterial pulse pressure in obese and normal-weight patients. METHODS: 15 morbidly obese patients undergoing LAGB were compared to 15 normal-weight patients undergoing laparoscopic surgery. Arterial pressure was non-invasively recorded using an arterial tonometer. Respiratory changes in pulse pressure (deltaPp) were recorded in the supine position without and with PNP, and in RT position with pneumoperitoneum. RESULTS: PNP increased deltaPp values in normal weight (P<0.001), but not in obese patients. RT position increased deltaPp values in obese patients, but did not cause additional changes in normal-weight patients. CONCLUSIONS: Unlike normal-weight patients, PNP in the supine position has minimal effect on the arterial pulse-pressure wave-form in obese patients. This observation may reflect physiological differences in total blood volume and loading conditions of the heart between morbidly obese and normal-weight patients, which affect venous return during PNP. Differences in abdominal vascular zone conditions between obese and normal weight-patients may explain these results.

Impaired alpha1-adrenergic responses in aged rat hearts.

To determine age-related changes in the cardiac effect of alpha1-adrenergic stimulation, both cardiomyocyte Ca2+-transient and cardiac protein kinase C (PKC) activity were measured in 3-month- (3MO) and 24-month- (24MO) old Wistar rats. Ca2+ transients obtained under 1 Hz pacing by microfluorimetry of cardiomyocyte loaded with indo-1 (405/480 nm fluorescence ratio) were compared in control conditions (Kreb's solution alone) and after alpha1-adrenergic stimulation (phenylephrine or cirazoline, an alpha1-specific agonist). PKC activity and PKC translocation index (particulate/total activity) were also assayed before and after alpha1-adrenergic stimulation. In 3MO, cirazoline induced a significant increase in Ca2+ transient for a 10(-9) M concentration which returned to control values for larger concentrations. In contrast, in 24MO, we observed a constant negative effect of cirazoline on the Ca2+ transient with a significant decrease at 10(-6) M compared with both baseline and Kreb's solution. Preliminary experiments showed that, in a dose-response curve to phenylephrine, the response of Ca2+ transient was maximal at 10(-7) M. This concentration induced a significant increase in Ca2+ transient in 3MO and a significant decrease in 24MO. The same concentration was chosen to perform PKC activity measurements under alpha1-adrenergic stimulation. In the basal state, PKC particulate activity was higher in 24MO than that in 3MO but was not different in cytosolic fractions; so that the translocation index was higher in 24MO (P < 0.01). After phenylephrine, a translocation of PKC toward the particulate fraction was observed in 3MO but not in 24MO. In conclusion, cardiac alpha1-adrenoceptor response was found to be impaired in aged hearts. The negative effect of alpha1-adrenergic stimulation on Ca2+ transient in cardiomyocytes obtained from old rats can be related to an absence of alpha1-adrenergic-induced PKC translocation.

The clinical relevance of systolic pressure variations in anesthetized nonhypotensive patients.

OBJECTIVE: To assess the accuracy of respiratory-induced systolic pressure variation and its components to detect low left ventricular preload. DESIGN: Prospective study. SETTING: University hospital. PARTICIPANTS: Sixty-seven patients undergoing major surgery under general anesthesia. INTERVENTIONS: Transesophageal echocardiographic measurements during apnea and mechanical ventilation. MEASUREMENTS AND MAIN RESULTS: Respiratory-induced systolic pressure variation and its components and left ventricular end-diastolic area obtained by transesophageal echocardiography were noted simultaneously. Arterial pressure indices did not allow a reliable diagnosis of a low left ventricular end-diastolic area using a cut-off value of 7.9 cm(2)/m(2) (inferior boundary of the interquartile range of the areas measured in the authors' group). CONCLUSIONS: These results suggest that systolic pressure variations noticed after induction of general anesthesia do not reflect low left ventricular preload in nonhypotensive patients.

Airway management using the intubating laryngeal mask airway for the morbidly obese patient.

UNLABELLED: We studied the effectiveness of the intubating laryngeal mask airway (ILMA) in morbidly obese patients scheduled for bariatric surgery. We included 118 consecutive morbidly obese patients (body mass index, 45 +/- 5 kg/m(2)). After the induction of general anesthesia, the laryngeal view was classified by the first observer according to the method of Cormack and Lehane. The ILMA was then inserted, and the trachea was intubated through the ILMA by a second observer. The rate of successful tracheal intubation with ILMA was 96.3%. The success rate, the number of attempts, and the total duration of the procedure were not different among patients with low-grade (Cormack 1-2) and patients with high-grade (Cormack 3-4) laryngeal views. The time required for insertion of the ILMA was slightly longer in patients with high-grade laryngeal views. Failures of the technique were not explained by the experience of the practitioner or airway characteristics. No adverse effect related to the technique was reported. Results of this study suggest that using the ILMA provides an additional technique for airway management of morbidly obese patients. IMPLICATIONS: The intubating laryngeal mask airway (ILMA) provides an additional technique for airway management of morbidly obese patients. The best choice of the primary technique (laryngoscopy or ILMA) for tracheal intubation of an adult obese patient remains to be determined.

Role of creatine kinase in cardiac excitation-contraction coupling: studies in creatine kinase-deficient mice.

To understand the role of creatine kinase (CK) in cardiac excitation-contraction coupling, CK-deficient mice (CK-/-) were studied in vitro and in vivo. In skinned fibers, the kinetics of caffeine-induced release of Ca2+ was markedly slowed in CK-/- mice with a partial restoration when glycolytic substrates were added. These abnormalities were almost compensated for at the cellular level: the responses of Ca2+ transient and cell shortening to an increased pacing rate from 1 Hz to 4 Hz were normal with a normal post-rest potentiation of shortening. However, the post-rest potentiation of the Ca2+ transient was absent and the cellular contractile response to isoprenaline was decreased in CK-/- mice. In vivo, echocardiographically determined cardiac function was normal at rest but the response to isoprenaline was blunted in CK-/- mice. Previously described compensatory pathways (glycolytic pathway and closer sarcoplasmic reticulum-mitochondria interactions) allow a quasi-normal SR function in isolated cells and a normal basal in vivo ventricular function, but are not sufficient to cope with a large and rapid increase in energy demand produced by beta-adrenergic stimulation. This shows the specific role of CK in excitation-contraction coupling in cardiac muscle that cannot be compensated for by other pathways.

Prediction of arterial oxygen tension during one-lung ventilation: analysis of preoperative and intraoperative variables.

OBJECTIVE: To determine whether currently available preoperative and intraoperative variables related to arterial oxygen tension (PaO(2)) can be used as predictors for low PaO(2) during one-lung ventilation (OLV). DESIGN: A prospective cohort study. SETTING: Primary university hospital. PARTICIPANTS: Adult patients (n = 92) undergoing thoracic surgery requiring OLV. INTERVENTIONS: Preoperative and intraoperative data, including past medical history, physical examination, and usual preoperative and intraoperative tests, were collected and used as explanatory variables for PaO(2) during OLV by univariate and multivariate analysis. A stepwise logistic regression including the same independent variables was used to identify patients who should be expected to develop arterial hypoxemia (PaO(2) <70 mmHg). Arterial blood gas samples were analyzed 15 minutes after the onset of OLV and after thoracotomy to determine the lowest PaO(2) value during OLV. MEASUREMENTS AND MAIN RESULTS: Preoperative (age, hematocrit, relative perfusion of the nondependent lung) and intraoperative (PaO(2) during 2-lung ventilation and mean arterial pressure at the lowest PaO(2)) variables were identified as independent factors affecting PaO(2) in OLV. PaO(2) during 2-lung ventilation was the only independent variable accounting for arterial hypoxemia when multivariate logistic regression was performed. CONCLUSION: The PaO(2) during OLV can be predicted using routinely available preoperative and intraoperative data. From a clinical point of view, this study failed to identify patients at risk of arterial hypoxemia when OLV is instituted because mainly intraoperative independent variables are involved in the decrease of PaO(2) in this situation.